poj1733 Parity game

#include <algorithm>
#include <iostream>
#include <cstdio>
using namespace std;
int n, m, num[10005], qwq=1, fa[10005], dis[10005];
char ss[15];
struct Node{
    int l, r, ans;
}nd[5005];
int myfind(int x){
    if(x==fa[x])    return x;
    int rot=myfind(fa[x]);
    dis[x] ^= dis[fa[x]];
    return fa[x]=rot;
}
int main(){
    cin>>n>>m;
    n = 0;
    for(int i=1; i<=m; i++){
        scanf("%d %d %s", &nd[i].l, &nd[i].r, ss);
        nd[i].l--;
        nd[i].ans = ss[0]==‘o‘;
        num[++n] = nd[i].l;
        num[++n] = nd[i].r;
    }
    sort(num+1, num+1+n);
    n = unique(num+1, num+1+n) - num - 1;
    for(int i=1; i<=m; i++){
        nd[i].l = lower_bound(num+1, num+1+n, nd[i].l) - num;
        nd[i].r = lower_bound(num+1, num+1+n, nd[i].r) - num;
    }
    for(int i=1; i<=n; i++) fa[i] = i;
    for(int i=1; i<=m; i++){
        int r1=myfind(nd[i].l), r2=myfind(nd[i].r);
        if(r1==r2){
            if(nd[i].ans!=(dis[nd[i].l]^dis[nd[i].r]))  break;
        }
        else{
            fa[r1] = r2;
            dis[r1] = dis[nd[i].l] ^ dis[nd[i].r] ^ nd[i].ans;
        }
        qwq++;
    }
    printf("%d\n", qwq-1);
    return 0;
}